[llvm] [VPlan] Always set flags for overflowing ops etc via VPIRFlags. (PR #179138)

[Florian Hahn via llvm-commits]

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@@ -3009,8 +3001,9 @@ static VPRecipeBase *optimizeMaskToEVL(VPValue *HeaderMask,
     Type *Ty = TypeInfo.inferScalarType(CurRecipe.getVPSingleValue());
     VPValue *ZExt =
         VPBuilder(&CurRecipe).createScalarCast(Instruction::ZExt, &EVL, Ty, DL);
-    return new VPInstruction(Instruction::Sub,
-                             {ZExt, Plan->getConstantInt(Ty, 1)}, {}, {}, DL);
+    return new VPInstruction(
+        Instruction::Sub, {ZExt, Plan->getConstantInt(Ty, 1)},
+        VPIRFlags::getDefaultFlags(Instruction::Sub), {}, DL);
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fhahn wrote:

Unfortunately `Builder` cannot be used here at the moment, as the caller inserts the instruction (we could unset the insert point....)

https://github.com/llvm/llvm-project/pull/179138